Struggling with Austin's allergies

At 6 months Austin had a anaphylaxis reaction to formula (milk). We saw an Allergist and conducted and blood test. Then a couple weeks later we conducted a skin test. We knew from those two tests that Austin was definitely allergic to milk, peanuts, and tree nuts. What we didn't know was that he would also be allergic to soy and wheat.
I have been doing lots of research. Did you know there are 8 main things that someone can be deathly allergic too? Austin is deathly allergic to 3 out of the 8 and has diarrhea and bad eczema from 2 more of the 8. So basically we have to avoid 5 out of the 8. I guess I never thought about how this would affect us on an ongoing basis, but as he gets closer to a year and starts eating "table scraps" I am realizing that this is going to be a big struggle.
John tells me "he will outgrow some", which is a good way to think, but what do we do NOW?? I mean Austin won't get tested again until next March, so until then we are on strict orders for TOTAL AVOIDANCE. We can hope that he outgrows some, but then they can come back.
I'm not sure where to proceed from here. Do we rid our house of everything he is allergic too?? I don't know how to eat that way... have you ever been to a store and had to read EVERY food label on EVERY food before you put it in your cart? Its EXHAUSTING. Even if it says "Processed in a facility with _______" or "may contain ____" we cannot buy it. Milk and nuts are in random things that you would never think about, like dried fruit. The list goes on... There are tons of foods out there that are gluten free. I have looked at the labels, almost all of them contain nuts or eggs. The problem isn't what he is allergic to but the combination. You can avoid one or the other, but trying to avoid all 5 is near impossible without eating fruits, vegetables, and meats only.
How do you cook without butter? without flour? without eggs? (We are to avoid eggs for now because the doctor thinks he is allergic and we don't want to test it and end up in the ER again). Also we need avoid sesame seeds, strawberries, acid fruit, ... because these are foods that cause lots of food allergies and to be on the safe side we aren't to give them to him.
For now Austin eats mostly pureed foods, and thankfully there are lots that I can find at the store that are organic that he can eat. I just know one day soon he will want to feed himself and then I really don't know what we will do.
I went to a friends house and she was trying to give Austin some food. I know she was just being helpful but it really opened my eyes. I asked to look at the package of everything and I could tell she was getting a little annoyed with me. Her kids don't have allergies, so she doesn't understand. At one point she said "you have an epi-pen don't you? just give it to him and see what happens". I'm saying this not to put her down, but because I think lots of people feel this way. I know I used to, what is the big deal, who cares. What she doesn't realize and I never did either is that it is Life and Death. People DIE from eating things they are allergic too. Now what I have the hardest time wrapping my brain around is why can Austin die from milk, peanuts, and tree nuts; but almost everyone else in the world can eat them without a second thought.
I know I'm rambling, but I just have to get this out. Our lives will forever be changed because of this. I think some of it is good. I'm sure John and I eat too much processed food, which we will have to remove from our house because of Austin's allergies. The hard part comes when we go to someones house or we go out to eat. Its almost impossible to ensure that the restaurant takes as much care as I do to make sure Austin's food doesn't come in contact with something that we eat that could cause a reaction.
Its summer now and so many people are having birthday parities and cook outs. For now we can go becuase I can bring Austin's food and he isn't mobile. What do we do next year when he is walking around and eating things off the floor? I can't watch him at ALL times. Do we just not go??? I have a friend who's child is so allergic to peanuts if you've had peanuts within 24 hours and washed your hands and touch him, he can still have a reaction. Austin is not that bad, but my friend goes to our church. Her son will be 2 this weekend and now that he is mobile they no longer stay for pot lucks at church. Her son only has a peanut allergy. What will we do?? I mean Austin is allergic to FIVE main ingredients in things. I don't want to be anti-social but will we have to avoid social gatherings with foods for a while until Austin is old enough to understand what he can and can't eat.
I'm going crazy, as you can very well see. I'm stopping the madness now, but this is what goes through my mind constantly. Hopefully we will learn as we go and we won't have anymore ER visits.